Updated FML:
MinecraftForge/FML@bc64ceabef76b1f4667b22ca8241b72351b44338 Optional shouldn't be constructable itself. It's purely a wrapper thing.
MinecraftForge/FML@55525f6d2eb24f42c26a291b8ce98feb4d4498c9 ModLoader is officially deprecated. It will all cease to be with 1.7.